The role of Mediterranean wetlands in climate regulation and greenhouse gases exchanges: from carbon biogeochemistry to European water and nature Directives

Atesa la seua alta activitat biogeoquímica, els aiguamolls són un dels tipus d'ecosistemes més actius en el cicle global del carboni, amb altes taxes d'intercanvi de carboni i de gasos d'efecte hivernacle (GEH), i, per tant, un gran potencial de regulació climàtica. Una de les parts més importants de la biogeoquímica del carboni als aiguamolls està lligada a les taxes metabòliques, a partir del coneixement de les quals es pot determinar un balanç de carboni associat amb el potencial intercanvi de carboni amb l'atmosfera. La seua capacitat per retindre carboni i mitigar el canvi climàtic, o, per contra, d'alliberar més GEH, i contribuir a l'escalfament global, es determina pel balanç de carboni i per les formes en què es produeixen les emissions de GEH-carbonats (CO2 o CH4), les quals estan relacionades amb multitud de factors ambientals. Aquesta tesi pretén abordar el funcionament dels aiguamolls mediterranis, que inclouen una gran varietat de llacs somers, estanys, i altres tipus de zones humides lenítiques, permanents o temporals, des d'una perspectiva metabòlica, per definir els mecanismes que regulen el balanç de carboni, en una zona geogràfica-climàtica fins ara escassament considerada en les estimacions globals del cicle de carboni. El principal objectiu d'aquesta tesi ha sigut ser determinar, per als principals tipus ecològics d'aiguamolls mediterranis, les taxes dels processos metabòlics lligats al balanç de carboni, i als intercanvis de GEH, així com la seua relació amb les variables ambientals, la salut ecològica, i els tipus principals d'alteracions. Els nostres resultats van mostrar una notable capacitat de retenció de carboni per part d’aquests ecosistemes, que va variar entre els diferents tipus ecològics, amb patrons associats a certs factors ambientals, com els hidrològics, l'estat tròfic, i la salinitat. Alteracions de tipus hidromorfològic, tròfic o de la salinitat de l'aigua, van comportar una pèrdua important de la capacitat de retenció de carboni i un augment en l'emissió dels GEH respecte a tipus ecològics similars, però ben conservats. Seguint els procediments de la Directiva Marc de l'Aigua i la Directiva Hàbitats per a l'avaluació de l'estat ecològic i de conservació, respectivament, i com a darrer gran objectiu de la tesi, es van avaluar ambdós estats per als 62 aiguamolls estudiats, i aquests estats es van relacionar amb les taxes i balanços metabòlics dels principals processos del cicle del carboni. Aquesta anàlisi conjunta va mostrar una correlació clara entre l'estat (ecològic o de conservació) i la capacitat de mitigació del canvi climàtic, de manera que els sistemes més degradats tendeixen, generalment, a alliberar carboni i, sobretot, a generar potencial d'escalfament, mentre que la bona salut ecològica d’aquests ecosistemes s’associa a una major capacitat de segrest de carboni i de mitigació del canvi climàtic. Els nostres resultats demostren la utilitat d'aquestes avaluacions per, també, i d'una manera indirecta, avaluar el paper potencial dels aiguamolls en la regulació climàtica a través de la determinació del seu estat, constituint un lligam entre les polítiques de conservació i gestió amb les polítiques climàtiques, el que permetrà dissenyar estratègies sinèrgiques de conservació i restauració d'aquests ecosistemes que afegisquen, a més, una perspectiva climàtica.Given their high biogeochemical activity, wetlands are one of the most active ecosystem types in the global carbon cycle, with high rates of carbon and greenhouse gas (GHG) exchange, and thus, a great potential for climate regulation. One of the most important parts of the carbon biogeochemistry in water is linked to the metabolic rates. Their knowledge makes possible to determine a balance of carbon associated with the exchange potential of carbon in the atmosphere. Their capacity to retain carbon and mitigate climate change, or, on the contrary, to release more GHGs and contribute to global warming, is determined by their carbon balance, and by the ways in which carbon-GHG emissions (CO2 or CH4) are produced, which are related to a multitude of environmental factors. This thesis aims to address the functioning of Mediterranean wetlands, which include a wide variety of shallow lakes, ponds, and other types of lentic wetlands, both permanent and temporary, from a metabolic perspective, to define the mechanisms that regulate their carbon balance, in a geographic-climatic area, so far scarcely considered in global estimates of the carbon cycle. The main objective of this thesis was to determine, for the main ecological types of Mediterranean wetlands, the rates of metabolic processes linked to the carbon balance and GHG exchanges, as well as their relationship with environmental variables, their ecological health, and the main types of alterations. Our results showed the remarkable carbon sequestration capacity of these ecosystems, which varied among the different ecological types, with patterns associated with certain environmental factors, such as hydrological factors, the trophic status, and salinity. Hydro-morphological, trophic or water salinity alterations led to a significant loss of their carbon retention capacity and an increase in GHG emissions compared to similar, but well-preserved ecological types. Following the procedures of the Water Framework Directive and the Habitats Directive for the assessment of ecological and conservation status, respectively, and as the final major objective of the thesis, both statuses were assessed for the 62 wetlands studied, and these statuses were related to the metabolic rates and balances of the main processes of the carbon cycle. This combined analysis showed a clear correlation between the (ecological and conservation) status and climate change mitigation capacity, such that more degraded systems generally tend to release carbon and, above all, generate warming potential, while the good ecological health of these ecosystems is associated with a higher carbon sequestration and climate change mitigation capacity. Our results demonstrate the usefulness of these assessments to also, indirectly, evaluate the potential role of wetlands in climate regulation through the determination of their status, providing a link between conservation and management policies and climate policies. This will allow the design of synergistic strategies for the conservation and restoration of these ecosystems which also add a climate perspective

La Moneda en el Área Rural de Ebusus (siglos IV-I a.C.)

El estudio y catalogación de la colección de monedas donadas por A. Martín al MAEF en 1991, procedente de hallazgos esporádicos en un medio rural ibicenco, ha permitido conocer mejor cómo estaba formada la masa monetaria en Ebusus entre los siglos V-IV y el I a.C. Durante este período la producción monetaria de Ebusus cubrió, casi en su totalidad, las necesidades monetarias de bronce de la isla. La nueva muestra también ratifica los niveles de producción en cada uno de los diversos períodos en los que se agrupa, así como la inexistencia de diferencias entre la moneda de bronce utilizada en un entorno urbano y de necrópolis y la que se empleó en ámbitos rurales y periurbanos. Por su tamaño y peso fue una moneda inapropiada para cubrir pagos de considerable cuantía, dado su reducido valor, pero pone de manifiesto la intensa y temprana monetización de Ebusus ya desde el pleno siglo III a.C. The study of the collection of coins presented by A. Martin to the MAEF, in 1991, coming from sporadic findings in rural areas of ibiza, has allowed us to improve our knowledge about the coinages circulating in Ebusus, between the 5th/4th centuries BC and the 1st BC. During this period the monetary output of Ebusus covered, almost in its totality the bronze monetary needs of the island. The new collection also ratifies the levels of production in every period in which coins are grouped. The sample also attested the nonexistence of differences between the bronze coins used in an urban media and in necropolis and those that were used in rural and periurban context. By its size and weight it was an unsuitable coinage to cover payments with considerable quantity, due to his reduced value, but they show the intense and early monetization of Ebusus, already from early 3rd century BC

Development of Inductive Sensor for Control Gate Opening of an Agricultural Irrigation System

© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.[EN] The monitoring of water level in the agriculture irrigation channels is essential to control the opening gates of these channels. In this way, WSNs (Wireless Sensor Networks) have high relevance to obtain this kind of data. In this paper, we propose a sensor to measure the depth changes in irrigation channels to control the gates opening. It is connected to an Adafruit Feather HUZZAH based on ESP8266, which allows us to build a mobile edge computing system. The developed sensor is based on two coils. Sinus-wave powers the first one, and the second is induced. The coils are winding over a polyvinyl chloride (PVC) that has high resistance for corrosion and low price. Besides, we use copper wire as a conductive metal. We test two different configurations of coils. P1 has five spires for the powered coil (PC) and ten spires for the induced coil (IC). On the other hand, P2 has 40 spires for the PC and 80 spires for the IC. The two prototypes were coiled in one layer. Then, both sensors are tested using a glass bottle where the water column increased with the target to obtain the information of the depth. In both prototypes, the difference of voltage between the maximum and minimum studied depths is more or less the same, 4.46V for P1 and 4.44V for P2. Nevertheless, during the stabilization test, the P1 showed better adaptation for the turbulences than the P2. The P1 shows an oscillation of 0.48V, where the P2 has a maximum fluctuation of 3.2V.This work has been partially supported by European Union through the ERANETMED (Euromediterranean Cooperation through ERANET joint activities and beyond) project ERANETMED3-227 SMARTWATIR by the Conselleria de Educacion, Cultura y Deporte with the Subvenciones para la contratacion de personal investigador en fase postdoctoral, grant number APOSTD/2019/04, and through the "Ayudas para contratacion predoctoral de Formacion del Profesorado Universitario FPU (Convocatoria 2016)". Grant number FPU16/05540.Basterrechea-Chertudi, DA.; Rocher-Morant, J.; Parra-Boronat, L.; Lloret, J. (2020). Development of Inductive Sensor for Control Gate Opening of an Agricultural Irrigation System. IEEE. 250-255. https://doi.org/10.1109/FMEC49853.2020.9144810S25025

Testing Existing Prototypes of Conductivity Sensors for Monitoring the Concentration of Organic Fertilizers in Fertigation Systems

[EN] Agricultural production has grown in recent years, increasing the use of Organic Fertilizers (OF). For that reason, the use of these compounds must be controlled in fertigation water. In this paper, we test three prototypes, using different combinations of coils, to determine the amount of OF in the water. A coil is powered by a sine wave of 3.3 peak-to-peak Volts for inducing another coil. The objective of this system is to detect different kinds of problems that can cause incorrect fertilization, which affects the sustainability of agriculture. We present the tests to verify the proper functioning of the prototypes. We test our prototypes by means of different dilutions of OF. The used concentrations of OF are between 0 and 20 g/l. We measure the conductivity for each concentration and the output voltage of our prototypes. The results show that prototype 3 is the one that has the best performance, obtaining 1.47 V of difference between the maximum and minimum output voltage and a good correlation coefficient. Finally, a verification test is carried out; the average error in the different samples tested is 0.2212%.This work has been partially supported by the European Union through the ERANETMED (Euromediterranean Cooperation through ERANET joint activities and beyond) project ERANETMED3-227 SMARTWATIR, by ¿Ministerio de Educación, Cultura y Deporte¿, through the ¿Ayudas para contratacion pre-doctoral de Formación del Profesorado Universitario FPU (Convocatoria 2016)¿. Grant number FPU16/05540, and by Conselleria de Educación, Cultura y Deporte with the Subvenciones para la contratación de personal investigador en fase postdoctoral, grant number APOSTD/2019/04.Basterrechea-Chertudi, DA.; Rocher-Morant, J.; Parra-Boronat, L.; Lloret, J. (2020). Testing Existing Prototypes of Conductivity Sensors for Monitoring the Concentration of Organic Fertilizers in Fertigation Systems. IARIA XPS Press. 50-55. http://hdl.handle.net/10251/178037S505

Low-Cost System Based on Optical Sensor to Monitor Discharge of Industrial Oil in Irrigation Ditches

[EN] Uncontrolled dumping linked to agricultural vehicles causes an increase in the incorporation of oils into the irrigation system. In this paper, we propose a system based on an optical sensor to monitor oil concentration in the irrigation ditches. Our prototype is based on the absorption and dispersion of light. As a light source, we use Light Emitting Diodes (LEDs) with different colours (white, yellow, blue, green, and red) and a photodetector as a sensing element. To test the sensor's performance, we incorporate industrial oils used by a diesel or gasoline engine, with a concentration from 0 to 0.20 mL(oil)/cm(2). The experiment was carried out at different water column heights, 0 to 20 cm. According to our results, the sensor can differentiate between the presence or absence of diesel engine oil with any LED. For gasoline engine oil, the sensor quantifies its concentration using the red light source; concentrations greater than 0.1 mL(oil)/cm(2) cannot be distinguished. The data gathered using the red LED has an average absolute error of 0.003 mL(oil)/cm(2) (relative error of 15.8%) for the worst case, 15 cm. Finally, the blue LED generates different signals in the photodetector according to the type of oil. We developed an algorithm that combines (i) the white LED, to monitor the presence of oil; (ii) the blue LED, to identify if the oil comes from a gasoline or diesel engine; and (iii) the red LED, to monitor the concentration of oil used by a gasoline engine.This work is partially funded by the "Ayudas para contratacion pre-doctoral de Formacion del Profesorado Universitario FPU (Convocatoria 2016)" grant number FPU16/05540. Conselleria de Educacion, Cultura y Deporte with the Subvenciones para la contratacion de personal investigador en fase postdoctoral, grant number APOSTD/2019/04, by the European Union, through the ERANETMED (Euromediterranean Cooperation through ERANET joint activities and beyond) project ERANETMED3-227 SMARTWATIR.Basterrechea-Chertudi, DA.; Rocher-Morant, J.; Parra-Boronat, L.; Lloret, J. (2021). Low-Cost System Based on Optical Sensor to Monitor Discharge of Industrial Oil in Irrigation Ditches. Sensors. 21(16):1-21. https://doi.org/10.3390/s21165449S121211

Development of a Low-Cost Optical Sensor to Detect Eutrophication in Irrigation Reservoirs

[EN] In irrigation ponds, the excess of nutrients can cause eutrophication, a massive growth of microscopic algae. It might cause different problems in the irrigation infrastructure and should be monitored. In this paper, we present a low-cost sensor based on optical absorption in order to determine the concentration of algae in irrigation ponds. The sensor is composed of 5 LEDs with different wavelengths and light-dependent resistances as photoreceptors. Data are gathered for the calibration of the prototype, including two turbidity sources, sediment and algae, including pure samples and mixed samples. Samples were measured at a different concentration from 15 mg/L to 4000 mg/L. Multiple regression models and artificial neural networks, with a training and validation phase, are compared as two alternative methods to classify the tested samples. Our results indicate that using multiple regression models, it is possible to estimate the concentration of alga with an average absolute error of 32.0 mg/L and an average relative error of 11.0%. On the other hand, it is possible to classify up to 100% of the samples in the validation phase with the artificial neural network. Thus, a novel prototype capable of distinguishing turbidity sources and two classification methodologies, which can be adapted to different node features, are proposed for the operation of the developed prototype.This work is partially funded by the Ministerio de Educacion, Cultura y Deporte through the"Ayudas para contratacion pre-doctoral de Formacion del Profesorado Universitario FPU (Convocatoria 2016)" grant number FPU16/05540 and by the Conselleria de Educacion, Cultura y Deporte through the "Subvenciones para la contratacion de personal investigador en fase postdoctoral", grant number APOSTD/2019/04.Rocher-Morant, J.; Parra-Boronat, L.; Jimenez, JM.; Lloret, J.; Basterrechea-Chertudi, DA. (2021). Development of a Low-Cost Optical Sensor to Detect Eutrophication in Irrigation Reservoirs. Sensors. 21(22):1-20. https://doi.org/10.3390/s21227637S120212

Ceratophyllum demersum L. as Phytoindicator and Potential Phytoremediator of Lead Under Hydroponic Conditions

[EN] The contamination of water by heavy metals like Pb is a huge problem for the environment. In this paper, we test Ceratophyllum demersum L. plants as phytoindicator. These were exposed to different concentrations of Pb for 1¿21 days, under hydroponic conditions, where they exhibited both adsorption and absorption efficiency. These efficiencies influenced in concentration and duration in a dependent manner. For the three initial treatments 0.125, 0.250, 0.500 ¿g/ml, the values of regression coefficients described the occurred variance on the rapid decrease in the Pb concentration in the hydroponic media, reflecting highest removal efficiency by C. demersum. Significant variation (P< 0.05) was recorded between the concentration of Pb accumulated in C. demersum at 0.125 and 0.250 ¿g/ml, while a highly significant value (P< 0.01) was recorded between them at 0.500 ¿g/ml. The regression coefficient denotes the pronounced impact of treatment concentration on the accumulation rate (R^2 = 0.9987). The adsorption efficiency of C. demersum appeared to be influenced by the Pb hydroponic media concentration, where after 21 days, the higher Pb adsorption was recorded at 0.125 ¿g/ml and the lowest one was obtained at 0.500 ¿g/ml. Results suggest that plants responded positively to the increase of Pb concentrations and they accumulated a high amount of metal. Due to metal removal coupled with detoxification potential, the plant appears to have potential for its use as phytoremediator species in aquatic environments.This work has been partially supported by the European Union through the ERANETMED (Euromediterranean Cooperation through ERANET joint activities and beyond) project ERANETMED3-227 SMARTWATIR by the Ministerio de Educación, Cultura y Deporte, through the Ayudas para contratacion predoctoral de Formación del Profesorado Universitario FPU (Convocatoria 2016). Grant number FPU16/05540.Fawzy, M.; El-Khatib, A.; Badr, N.; Abo-El-Kasem, A.; Rocher-Morant, J.; Basterrechea-Chertudi, DA. (2019). Ceratophyllum demersum L. as Phytoindicator and Potential Phytoremediator of Lead Under Hydroponic Conditions. IARIA XPS Press. 20-26. http://hdl.handle.net/10251/180618S202

Design and Calibration of Moisture Sensor Based on Electromagnetic Field Measurement for Irrigation Monitoring

[EN] Soil moisture control is crucial to assess irrigation efficiency in green areas and agriculture. In this paper, we propose the design and calibration of a sensor based on inductive coils and electromagnetic fields. The proposed prototypes should meet a series of requirements such as low power consumption, low relative error, and a high voltage difference between the minimum and maximum moisture. We tested different prototypes based on two copper coils divided into two different sets (P1-P15 and NP1-NP4). The prototypes have different characteristics: variations in the number and distribution of spires, existence or absence of casing, and copper wires with a diameter of 0.4 or 0.6 mm. In the first set of experiments carried out in commercial soil, the results showed that the best prototypes were P5, P8, and P9. These prototypes were used in different types of soils, and P8 was selected for the subsequent tests. We carried the second set of experiments using soil from an agricultural field. Based on the data gathered, mathematical models for the calibration of prototypes were obtained and verified. In some cases, two equations were used for different moisture intervals in a single prototype. According to the verification results, NP2 is the best prototype for monitoring the moisture in agricultural lands. It presented a difference in induced voltage of 1.8 V, at 500 kHz, between wet and dry soil with a maximum voltage of 5.12 V. The verification of the calibration determined that the calibration using two mathematical models offers better results, with an average absolute error of 2.1% of moisture.This work is funded by the European Union under ERANETMED (Euro-Mediterranean Cooperation through ERANET joint activities and beyond), project ERANETMED3-227 SMARTWATIR and the European Union, MAPA and Comunidad de Madrid (through IMIDRA), under the project PDR18-XEROCESPED of the PDR-CM 2014-2020 (operative programme of the European Agriculture Fund for Rural Development, EAFRD). L.P. is funded by Conselleria de Educacion, Cultura y Deporte, programme Subvenciones para la contratacion de personal investigador en fase postdoctoral, grant APOSTD/2019/04; J.R. by the Ministerio de Educacion, Cultura y Deporte, through the "Ayudas para contratacion pre-doctoral de Formacion del Profesorado Universitario FPU (Convocatoria 2016)" grant number FPU16/05540; and M.P. by the Universitat Politecnica de Valencia through the pre-doctoral PAID-01-20 programme.Basterrechea-Chertudi, DA.; Rocher-Morant, J.; Parra-Boronat, M.; Parra-Boronat, L.; Marín, JF.; Mauri, PV.; Lloret, J. (2021). Design and Calibration of Moisture Sensor Based on Electromagnetic Field Measurement for Irrigation Monitoring. Chemosensors. 9(9):1-32. https://doi.org/10.3390/chemosensors9090251S1329

The underestimated role of carrion in vertebrates' diet studies

Aim: Despite the increasing scientific evidence on the importance of carrion in the ecology and evolution of many vertebrates, scavenging is still barely considered in diet studies. Here, we draw attention to how scientific literature has underestimated the role of vertebrates as scavengers, identifying the ecological traits that characterize those species whose role as scavengers could have gone especially unnoticed. Location: Global. Time Period: 1938–2022. Major Taxa Studied: Terrestrial vertebrate scavengers. Methods: We analysed and compared (a) the largest database available on scavenging patterns by carrion-consuming vertebrates, (b) 908 diet studies about 156 scavenger species and (c) one of the most complete databases on bird and mammal diets (Elton Traits database). For each of these 156 species, we calculated their scavenging degree (i.e. proportion of carcases where the species is detected consuming carrion) as a proxy for carrion consumption, and related their ecological traits with the probability of being identified as scavengers in diet studies and in the Elton Traits database. Results: More than half of the species identified as scavengers at monitored carcasses were not assigned carrion as food source in their diet studies nor in the Elton Traits database. Using a subset of study sites, we found a direct relationship between a species' scavenging degree and its rate of carrion biomass removal. In addition, scavenger species, which were classified as non-predators and mammals had a lower probability of being identified as scavengers in diet studies and in the Elton Traits database, respectively. Main Conclusions: Our results clearly indicate an underestimation of the role of scavenging in vertebrate food webs. Given that detritus recycling is fundamental to ecosystem functioning, we encourage further recognition and investigation of the role of carrion as a food resource for vertebrates, especially for non-predator species and mammals with higher scavenging degree.JM was supported by a Basque Government predoctoral grant (PRE_2018_2_0112), ZMR, LNA and EA by contracts co-funded by the Generalitat Valenciana and the European Social Fund (ESF) (APOSTD/2019/016, ACIF/2019/056 and APOSTD/2021/028 respectively). MM, JMPG and ESG were funded by MCIN/AEI/10.13039/501100011033, by ‘European Union NextGenerationEU/PRTR’, ERDF ‘A way of making Europe’ and by ESF ‘Investing in your future’ (grant numbers RYC-2015-19231, IJC-2019-038968, TED2021-130890B-C21, PID2021-128952NB-I00 and RYC-2019-027216-I). ESG was also partially funded by the HORIZONMSCA-2021-SE-0 action number: 101086387, ‘REMARKABLE’ project. ZMR and DRG were also funded by the Junta de Andalucía (POSTDOC_21_00353 and PREDOC_00262). RPR was co-funded by the ESF and Plan Propio I+D+i UCLM

Carbon metabolic rates and GHG emissions in different wetland types of the Ebro Delta

Deltaic wetlands are highly productive ecosystems, which characteristically can act as C-sinks. However, they are among the most threatened ecosystems, being very vulnerable to global change, and require special attention towards its conservation. Knowing their climate change mitigating potential, conservation measures should also be oriented with a climatic approach, to strengthen their regulatory services. In this work we studied the carbon biogeochemistry and the specific relevance of certain microbial guilds on carbon metabolisms of the three main types of deltaic wetlands located in the Ebro Delta, north-eastern Spain, as well as how they deal with human pressures and climate change effects. We estimated the metabolic rates of the main carbon-related metabolisms (primary production and respiration) and the resulting carbon and global warming potential balances in sites with a different salinity range and trophic status. With the results obtained, we tried to define the influence of possible changes in salinity and trophic level linked to the main impacts currently threatening deltaic wetlands, on the C-metabolisms and GHG emissions, for a better understanding of the mitigating capacity and their possible enhancement when applying specific management actions. Metabolic rates showed a pattern highly influenced by the salinity range and nutrients inputs. Freshwater and brackish wetlands, with higher nutrient inputs from agricultural runoff, showed higher C-capture capacity (around 220–250 g C m-2 y-1), but also higher rates of degradative metabolisms (aerobic respiration and CH4 emissions). Contrastingly, the rates of C-related metabolisms and C-retention of Salicornia-type coastal salt marshes were lower (42 g C m-2 y-1). The study of the microbial metacommunity composition by the16S RNA gene sequencing revealed a significant higher presence of methanogens in the salt marsh, and also higher metabolic potential, where there was significantly more organic matter content in sediment. Salinity inhibition, however, explained the lower respiration rates, both aerobic and anaerobic, and prevented higher rates of methanogenesis despite the major presence of methanogens. Conservation measures for these wetlands would require, overall, maintaining the sediment contributions of the river basin intending to overcome the regression of the Delta and its salt marshes in a climate change scenario. Particularly, for reducing degradative metabolisms, and favour C-retention, nutrient inputs should be controlled in freshwater and brackish wetlands in order to reduce eutrophication. In salt marshes, the reduction of salinity should be avoided to control increases in methanogenesis and CH4 emissions.info:eu-repo/semantics/publishedVersio